A federal judge overseeing Barry Bonds' criminal case says she'll likely exclude from trial three positive drug tests.

But she said she's inclined to keep a recorded conversation between Bonds' personal trainer and former personal assistant discussing steroid use.

U.S. District Judge Susan Illston said during an evidentiary hearing Thursday that her initial thoughts were to exclude the 2000-2001 positive tests seized by investigators during a BALCO raid unless there is direct testimony tying the urine samples to Bonds.

Bonds is charged with lying to a December 2003 grand jury when he said he never knowingly used performance-enhancing drugs. He pleaded not guilty to the charges earlier Thursday.

It was Bonds' third time pleading in the case. He originally was indicted in November 2007, but the government revised the charges twice to fix legal technicalities. The former San Francisco Giants slugger now faces 10 counts of making false statements to a grand jury, plus an obstruction of justice charge.

Bonds arrived for the hearing in a black SUV at the back of the courthouse under gray skies. Three bodyguards got out followed by Bonds, who was wearing a tan suit with a white shirt and a brown paisley tie.

He walked briskly down the sidewalk through the gathered reporters, giving them a polite "Good morning. How are you?" before entering the courthouse. Inside the courtroom, he was greeted by his aunt, who grabbed his hand and said "I love you sweetie."

After the arraignment, Bonds' case moved to a different courtroom, where lawyers for both sides were arguing about what evidence should be included during Bonds' upcoming trial, scheduled to start March 2.

If convicted, Bonds faces a sentence between probation and two years in prison.

U.S. District Judge Susan Illston unsealed on Wednesday hundreds of pages of documents that go to the core of the government's criminal case.

Bonds' legal team was asking Illston to exclude from trial drug test results they say are inconclusive and transcripts they claim are hearsay, among other evidence.

Investigators seized the results during their raid of the Bay Area Laboratory Co-Operative, known as BALCO, in September 2003. Prosecutors say the results show Bonds testing positive in 2000 and 2001.

Bonds' lawyers argue there is no way to know that the test results belong to Bonds because of shoddy collection, handling and processing of the urine and blood samples. The same so-called chain-of-custody argument was used by O.J. Simpson to help win an acquittal in his murder trial.

Bonds' attorneys also want the judge to exclude from trial transcripts of a conversation between Bonds' former personal trainer Greg Anderson and his former assistant Steve Hoskins.

The documents said Hoskins, Bonds' childhood friend, secretly tape-recorded a 2003 conversation with Anderson in the Giants' clubhouse because Hoskins wanted to prove to Bonds' father, Bobby Bonds, that his son was using steroids.

Anderson and Hoskins, who were near Bonds' locker, were discussing steroid injections, and at one point, they lowered their voices to avoid being overheard as players, according to the documents unsealed Wednesday.

Anderson's attorney Mark Geragos says his client will refuse to testify at trial, so the transcripts are the prosecution's chance to introduce his voice into their arguments.

But Bonds' attorneys argue that the slugger's right to confront witnesses will be violated if his attorneys can't question Anderson about the recording.